The gonadotropin-releasing hormone (GnRH), also referred to as luteinizing hormone-releasing hormone (LHRH), is a decapeptide that plays a key role in human reproduction. The hormone is released from the hypothalamus and acts on the pituitary gland to stimulate the biosynthesis and secretion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH). LH released from the pituitary gland is primarily responsible for the regulation of gonadal steroid production in both sexes, whereas FSH regulates spermatogenesis in males and follicular development in females. GnRH agonists and antagonists have proven effective in the treatment of certain conditions which require inhibition of LH/FSH release. In particular, GnRH-based therapies have proven effective in the treatment of endometriosis, uterine fibroids, polycystic ovarian disease, precocious puberty and several gonadal steroid-dependent neoplasia, most notably cancers of the prostate, breast and ovary. GnRH agonists and antagonists have also been utilized in various assisted fertilization techniques and have been investigated as a potential contraceptive in both men and women. They have also shown possible utility in the treatment of pituitary gonadotrophe adenomas, sleep disorders such as sleep apnea, irritable bowel syndrome, premenstrual syndrome, benign prostatic hyperplasia, hirsutism, as an adjunct to growth hormone therapy in growth hormone deficient children, and in murine models of lupus. The compounds of the invention may also be used in combination with bisphosphonates (bisphosphonic acids) and other agents, such as growth hormone secretagogues, e.g. MK-0677, for the treatment and the prevention of disturbances of calcium, phosphate and bone metabolism, in particular, for the prevention of bone loss during therapy with the GnRH antagonist, and in combination with estrogens, progesterones, antiestrogens, antiprogestins and/or androgens for the prevention or treatment of bone loss or hypogonadal symptoms such as hot flashes during therapy with the GnRH antagonist.
Additionally, a compound of the present invention may be co-administered with a 5.alpha.-reductase 2 inhibitor, such as finasteride or epristeride; a 5.alpha.-reductase 1 inhibitor such as 4,7.beta.-dimethyl-4-aza-5.alpha.-cholestan-3-one, 3-oxo-4-aza-4,7.beta.-dimethyl-16.beta.-(4-chlorophenoxy)-5.alpha.-androst ane, and 3-oxo-4-aza-4,7.beta.-dimethyl-16.beta.-(phenoxy)-5.alpha.-androstane as disclosed in WO 93/23420 and WO 95/11254; dual inhibitors of 5.alpha.-reductase 1 and 5.alpha.-reductase 2 such as 3-oxo-4-aza-17.beta.-(2,5-trifluoromethylphenyl-carbamoyl)-5.alpha.-andros tane as disclosed in WO 95/07927; antiandrogens such as flutamide, casodex and cyproterone acetate, and alpha-i blockers such as prazosin, terazosin, doxazosin, tamsulosin, and alfuzosin.
Further, a compound of the present invention may be used in combination with growth hormone, growth hormone releasing hormone or growth hormone secretagogues, to delay puberty in growth hormone deficient children, which will allow them to continue to gain height before fusion of the epiphyses and cessation of growth at puberty.
Current GnRH antagonists are GnRH-like decapeptides which are generally administered intravenously or subcutaneously presumably because of negligible oral activity. These have amino acid substitutions usually at positions one, two, three, six and ten.
Non-peptide GnRH antagonists offer the possible advantage of oral adminstration. Non-peptide GnRH antagonists have been described in European Application 0 219 292 and in De, B. et al., J. Med. Chem., 32, 2036-2038 (1989), in WO 95/28405, WO 95/29900 and EP 0679642 all to Takeda Chemical Industries, Ltd.
Arylquinolone analogs have been described in the art and include those described in the following patents, patent applications and journal articles. JP-A-63-295561 discloses a class of 3-phenyl-2(1H)-quinolone derivatives, substituted at the 4-position by an unsubstituted straight or branched alkoxy group and at the 7-position by an unsubstituted straight or branched alkoxy group. These compounds are alleged to exhibit a strong inhibitory action on bone resorption and a stimulatory effect on ossification, and thus to be useful as therapeutic agents for the prevention and treatment of osteoporosis.
J. Heterocycl. Chem., 1989, 26, 281 discloses a range of 3-(2-methoxyphenyl)-2(1H)-quinolones possessing a halogen substituent in the 6- or 7-position and an optional carboxylic acid substituent at the 4-position. A family of 3-phenyl-2(IH)-quinolone derivatives, substituted at the 4-position by an amino or benzylamino group and at the 7-position by a methyl or methoxy group, is described in Monatsh. Chem., 1982, 113, 751 and Vestn. Slov. Kem. Drus., 1986, 33, 271.
WO 93/10783 and WO 93/11115 disclose a class of 2-(1H)-quinolone derivatives, substituted at the 3-position by an optionally substituted aryl substituent and are selective non-competitive antagonists of NMDA receptors and/or are antagonists of AMPA receptors, and are therefore of utility in the treatment of conditions, such as neurodegenerative disorders, convulsions or schizophrenia.
FR 2711992-Al discloses quinolone derivatives which are allegedly useful as antagonists of platelet activating factor.